Propeller.



i G. 11111. ANTONI. y

Patented 116111.51911-- UNITED sTATEs IJTENT oEEIoE.

GUIDO ANTONI AND UGO ANTONI, OF PISA, ITALY.'`

PROPELLER.

i Specication of Letters Patent.

Patented sept. 5, 1911.

Application led December 30, 1208. Serial No. 470,112.

To all whom 'it may concern:

Be it known that we, GUIDO ANTONI, draftsman, and UGo ANTONI, employee, subjects of theKing of Italy, residing at No. 14 Lungarno Mediceo, Pisa, in the Kingdom of Italy, have invented new and useful Improvements in or Relating to Propellers, of which the following is a specification.

This invention relatesto that class of propellers which are provided with flexible blades. Experience has roved that theemployment of screws provided with very fiexible blades enables the pro ulsion of bodies in water or in air to be e ected much more efficiently than when screws having rigid' blades are used.

According to this invention the screw for .a ueous or aerial navigation is `provided with blades which become gradually thinner from the root to the t-ip and from the lea-ding edge to the following edge wherebyv there is obtained in the thinnest parts a very high degree of flexibility. A construction 'of propeller with flexible blades will now be described by way of example only.

A construction according to this invention is illustrated by way of example in the accompanying drawing, wherein Figure 1 represents the propeller blade in elevation and attached to -the propeller shaft; Fi' 2 is an edge view of the blade showing (Iiagrammatically the flexed forms which the Ablade is capable of assuming Aunder the influence of the medium upon,

which the blade acts. Figs. 3 and 4 represent sections-through the blades on the lines'- C-D and A-iB respectively, and showing how the blade diminishes in thickness in a direction fiom its root to its tip and from its leading edge to-its following edge.

a is the propeller shaft having a lcontinuous rotary movement. To its end are .se-

' cured by means of disks b having double at uniform angular distances about the axis it may be found suitable to secure the posiclamp plates z' adapt-ed to secure by means of bolts u, theyblades o of the propeller. The propeller can have a single blade as in the drawing, or it can have 2, 3 or 4. arranged of the shaft a. v

In the construction shown vin the drawing, during the erecting, the blade c with the disk `b can be turned about the bolt d, its in' clination being varied at will. This variabllity is not always necessary. 'In practice,

4tion of the blade '0, after having inclined it during construction to the extent which experience may show to be suitable. to thev conditions which the propeller will have to satisfy in each particular case.

The desired flexibility is obtained by'giving to 'the blade a gradually decreasing thickness'froin its roo-t or point of attachment to theI clamps toward its peripheral end or tip a z as well Ias from the leading edge 'w toward the following edge y where v -the flexibility is at the maximum.

Fig. 2 shows in dotted lines merely by way of illustration, the deformation which a blade of this system can experience in certain conditions of working.

The dimensions of the propeller and the degree of flexibility will vary of course in accordance with the work which the propeller hasto do, more particularly according to whetherthe propeller is intended to work kin water or in the air.-

We claim as our invention:

1. A propeller adapted for water or aerial navigation `comprising a driving hub and a blade rigidly and y lmmovably connected thereto and having a diminishing thickness in a direct-ion from its root to its periphery or tip and from its leading edge to its following edge which renders the thinner portions of the blade capable of flexing under the influence ofthe medium upon which the blade acts.

2. The combination of a propeller shaft, a propeller blade, and a mounting for adjustably con.\ecting such blade and shaft comprising' a clamp, a pivot arranged transverse to the axis of the shaft and connecting said clamp thereto whereby the pitch of the i nesses. l

ANTONI GUIDO. ANTONI UGO. Witnesses: f FILIPPO LAURO, DARIO Booornnno. 

